Hypoactive delirium (HD) is a major subtype of postoperative delirium (POD), which accounts for 50% in patients with general delirium. Patients who suffer from it have a higher risk of death and a worse prognosis. However, the understanding of postoperative HD is not adequate. This review systematically summarized the definition, incidence, risk factors and pathogenesis of POD, further addressed the clinical manifestations, risk factors, assessment, prevention and research advances of postoperative HD aims to improve patient's prognosis and reduce patients' economic cost.